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1.
Oncologist ; 24(6): e251-e259, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30139835

RESUMO

BACKGROUND: The VeriStrat test provides accurate predictions of outcomes in all lines of therapy for patients with non-small cell lung cancer (NSCLC). We investigated the predictive and prognostic role of VeriStrat in patients enrolled on the MARQUEE phase III trial of tivantinib plus erlotinib (T+E) versus placebo plus erlotinib (P+E) in previously treated patients with advanced NSCLC. METHODS: Pretreatment plasma samples were available for 996 patients and were analyzed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry to generate VeriStrat labels (good, VS-G, or poor, VS-P). RESULTS: Overall, no significant benefit in overall survival (OS) and progression-free survival (PFS) were observed for the addition of tivantinib to erlotinib. Regardless of treatment arm, patients who were classified as VS-G had significantly longer PFS (3.8 mo for T+E arm, 2.0 mo for P+E arm) and OS (11.6 mo for T+E, 10.2 mo for P+E arm) than patients classified as VS-P (PFS: 1.9 mo for both arms, hazard ratio [HR], 0.584; 95% confidence interval [CI], 0.468-0.733; p < .0001 for T+E, HR, 0.686; 95% CI, 0.546-0.870; p = .0015 for P+E; OS: 4.0 mo for both arms, HR, 0.333; 95% CI, 0.264-0.422; p < .0001 for T+E; HR, 0.449; 95% CI, 0.353-0.576; p < .0001 for P+E). The VS-G population had higher OS than the VS-P population within Eastern Cooperative Oncology Group (ECOG) performance score (PS) categories. VS-G patients on the T+E arm had longer PFS, but not OS, than VS-G patients on the P+E arm (p = .0108). Among EGFR mutation-positive patients, those with VS-G status had a median OS more than twice that of any other group (OS: 31.6 mo for T+E and 22.8 mo for P+E), whereas VS-P patients had similar survival rates as VS-G, EGFR-wild type patients (OS: 13.7 mo for T+E and 6.5 mo for P+E). CONCLUSION: In these analyses, VeriStrat showed a prognostic role within EGOC PS categories and regardless of treatment arm and EGFR status, suggesting that VeriStrat could be used to identify EGFR mutation-positive patients who will have a poor response to EGFR tyrosine kinase inhibitors. IMPLICATIONS FOR PRACTICE: This study suggests that VeriStrat testing could enhance the prognostic role of performance status and smoking status and replicates findings from other trials that showed that the VeriStrat test identifies EGFR mutation-positive patients likely to have a poor response to EGFR tyrosine kinase inhibitors (TKIs). Although these findings should be confirmed in other populations, VeriStrat use could be considered in EGFR mutation-positive patients as an additional prognostic tool, and these results suggest that EGFR mutation-positive patients with VeriStrat "poor" classification could benefit from other therapeutic agents given in conjunction with TKI monotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Proteômica/instrumentação , Kit de Reagentes para Diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Cloridrato de Erlotinib/farmacologia , Cloridrato de Erlotinib/uso terapêutico , Estudos de Viabilidade , Feminino , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Pirrolidinonas/farmacologia , Pirrolidinonas/uso terapêutico , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Estudos Retrospectivos , Adulto Jovem
2.
Antimicrob Agents Chemother ; 60(9): 5357-67, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27353263

RESUMO

Enterovirus 71 (EV-A71) is a major causative pathogen of hand, foot, and mouth disease (HFMD) epidemics. No antiviral therapies are currently available for treating EV-A71 infections. Here, we selected five reported enterovirus inhibitors (suramin, itraconazole [ITZ], GW5074, rupintrivir, and favipiravir) with different mechanisms of action to test their abilities to inhibit EV-A71 replication alone and in combination. All selected compounds have anti-EV-A71 activities in cell culture. The combination of rupintrivir and ITZ or favipiravir was synergistic, while the combination of rupintrivir and suramin was additive. The combination of suramin and favipiravir exerted a strong synergistic antiviral effect. The observed synergy was not due to cytotoxicity, as there was no significant increase in cytotoxicity when compounds were used in combinations at the tested doses. To investigate the potential inhibitory mechanism of favipiravir against enterovirus, two favipiravir-resistant EV-A71 variants were independently selected, and both of them carried an S121N mutation in the finger subdomain of the 3D polymerase. Reverse engineering of this 3D S121N mutation into an infectious clone of EV-A71 confirmed the resistant phenotype. Moreover, viruses resistant to ITZ or favipiravir remained susceptible to other inhibitors. Most notably, combined with ITZ, rupintrivir prevented the development of ITZ-resistant variants. Taken together, these results provide a rational basis for the design of combination regimens for use in the treatment of EV-A71 infections.


Assuntos
Antivirais/farmacologia , Enterovirus Humano A/efeitos dos fármacos , Isoxazóis/farmacologia , Itraconazol/farmacologia , Pirrolidinonas/farmacologia , Suramina/farmacologia , Proteínas não Estruturais Virais/genética , Amidas/farmacologia , Sequência de Aminoácidos , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Chlorocebus aethiops , Combinação de Medicamentos , Farmacorresistência Viral/genética , Sinergismo Farmacológico , Enterovirus Humano A/genética , Enterovirus Humano A/crescimento & desenvolvimento , Humanos , Indóis/farmacologia , Simulação de Acoplamento Molecular , Mutação , Mioblastos/efeitos dos fármacos , Mioblastos/virologia , Fenóis/farmacologia , Fenilalanina/análogos & derivados , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Estrutura Secundária de Proteína , Pirazinas/farmacologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Valina/análogos & derivados , Células Vero , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacos
3.
Rocz Panstw Zakl Hig ; 66(3): 281-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26400126

RESUMO

BACKGROUND: The ability of bacteria to develop common mechanisms of resistance to antibiotics and disinfectants raises doubts about the effectiveness of disinfection processes. Glucoprotamin (GP) is an antimicrobial active substance which is widely used to the disinfection in medical area. OBJECTIVE: The aim of study was to compare GP's effectiveness with susceptibility of reference strains used for the evaluation of bactericidal efficacy of disinfectants Staphylococcus aureus (S. aureus); Pseudomonas aeruginosa (P. aeruginosa) and standard antibiotic-resistant strains: meticillin-resistant S. aureus (MRSA) and tetracycline-resistant P. aeruginosa (PAO-LAC). MATERIAL AND METHODS: Minimum inhibitory concentrations (MICs) of GP and minimum bactericidal concentrations (MBCs) against tested strains were evaluated by serial broth dilution technique. GP's efficiency was examined according to qualitative (phenol coefficient GP-PC) and quantitative (EN 1040: 2006) test methods. RESULTS: Gram-negative strains were more tolerant to GP than Gram-positive strains among tested strains. MRSA and S. aureus exhibited similar susceptibility to GP. PAO-LAC had significantly lower susceptibility to GP than P. aeruginosa (P≤0,05). There were no differences in GP efficiency against these strains based on GP-PC. According to PN-EN 1040: 2006 standard average obligatory reduction≥5 log10 was demonstrated in the active concentration of GP (84 mg/l) at obligatory 5 min contact time for PAO-LAC and P. aeruginosa. The differences in basis bactericidal activity between PAO-LAC and P. aeruginosa were obtained in the active concentration at 10 and 15 min contact time (P≤0,05). CONCLUSIONS: Variation in a susceptibility of reference strains and antibiotic-resistant standard strains has no meaning at used clinically GP concentrations, which are higher than concentration causing basis bactericidal activity of GP.


Assuntos
Antibacterianos/farmacologia , Diaminas/farmacologia , Desinfetantes/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Pirrolidinonas/farmacologia , Infecção Hospitalar/prevenção & controle , Desinfecção/métodos , Resistência Microbiana a Medicamentos , Humanos , Testes de Sensibilidade Microbiana
4.
J Theor Biol ; 345: 61-9, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24378646

RESUMO

Combination Antiretroviral Therapy (cART) can suppress plasma HIV below the limit of detection in normal assays. Recently reported results suggest that viral replication may continue in some patients, despite undetectable levels in the blood. It has been suggested that the appearance of the circularized episomal HIV DNA artifact 2-LTR following treatment intensification with the integrase inhibitor raltegravir is a marker of ongoing viral replication. Other work has suggested that lymphoid organs may be a site of reduced antiviral penetration and increased viral production. In this study we model the hypothesis that this ongoing replication occurs in lymphoid follicle sanctuary sites and investigate the patterns of 2-LTR formation expected after raltegravir application. Experimental data is used to estimate the reaction and diffusion parameters in the model, and Monte-Carlo simulations are used to explore model behavior subject to variation in these rates. The results suggest that conditions for the formation of an observed transient peak in 2-LTR formation following raltegravir intensification include a sanctuary site diameter larger than 0.2mm, a viral basic reproductive ratio within the site larger than 1, and a total volume of active sanctuary sites above 20mL. Significant levels of uncontrolled replication can occur in the sanctuary sites without measurable changes in the plasma viral load. By contrast, subcritical replication (where the basic reproductive ratio of the virus is less than 1 in all sites) always results in monotonic increases of measured 2-LTR following raltegravir intensification, occurring at levels below the limit of detection.


Assuntos
Fármacos Anti-HIV/farmacologia , Infecções por HIV/virologia , Repetição Terminal Longa de HIV/efeitos dos fármacos , HIV-1/efeitos dos fármacos , Modelos Biológicos , Pirrolidinonas/farmacologia , Viremia/virologia , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , HIV-1/genética , HIV-1/isolamento & purificação , HIV-1/fisiologia , Humanos , Linfonodos/virologia , Método de Monte Carlo , Pirrolidinonas/administração & dosagem , Pirrolidinonas/uso terapêutico , Raltegravir Potássico , Carga Viral , Viremia/tratamento farmacológico , Replicação Viral/efeitos dos fármacos , Replicação Viral/genética
5.
Org Biomol Chem ; 10(28): 5343-6, 2012 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-22695979

RESUMO

A simple and efficient three components domino reaction of γ-butyrolactam (2-pyrrolidinone), aromatic aldehyde and substituted thiophenol catalyzed by elemental iodine resulted in the formation of 1-((phenylthio)(phenyl)methyl)pyrrolidin-2-one derivatives. The stability of the synthesized analogues was evaluated in stimulated gastric fluid (SGF) and bovine serum albumin (BSA). In vitro anticancer activity was investigated in the low micromolar range and a few analogues were found to possess good activity. This current protocol provides several advantages like shorter reaction time, excellent yield and convenient work-up.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Iodo/química , Pirrolidinonas/síntese química , Pirrolidinonas/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Catálise , Bovinos , Linhagem Celular Tumoral , Técnicas de Química Sintética/economia , Técnicas de Química Sintética/métodos , Humanos , Modelos Moleculares , Neoplasias/tratamento farmacológico , Pirrolidinonas/química , Pirrolidinonas/metabolismo , Soroalbumina Bovina/metabolismo
6.
J Med Chem ; 55(9): 4489-500, 2012 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-22500930

RESUMO

The effects of addition of a methyl group to a lead compound on biological activity are examined. A literature analysis of >2000 cases reveals that an activity boost of a factor of 10 or more is found with an 8% frequency, and a 100-fold boost is a 1 in 200 event. Four cases in the latter category are analyzed in depth to elucidate any unusual aspects of the protein-ligand binding, distribution of water molecules, and changes in conformational energetics. The analyses include Monte Carlo/free-energy perturbation (MC/FEP) calculations for methyl replacements in inhibitor series for p38α MAP kinase, ACK1, PTP1B, and thrombin. Methyl substitutions ortho to an aryl ring can be particularly effective at improving activity by inducing a propitious conformational change. The greatest improvements in activity arise from coupling the conformational gain with the burial of the methyl group in a hydrophobic region of the protein.


Assuntos
Proteína Quinase 14 Ativada por Mitógeno/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/química , Proteínas Tirosina Quinases/química , Trombina/química , Amidas/farmacologia , Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Modelos Moleculares , Simulação de Dinâmica Molecular , Método de Monte Carlo , Ligação Proteica , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Pirimidinas/farmacologia , Pirrolidinonas/farmacologia , Relação Estrutura-Atividade , Termodinâmica , Tiofenos/farmacologia , Trombina/antagonistas & inibidores , Trombina/metabolismo
7.
Clin Immunol ; 137(3): 347-56, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20832370

RESUMO

Four catechins with the galloyl moiety, including catechin gallate (CG), epigallocatechin gallate (EGCG), gallocatechin gallate (GCG), and epicatechin gallate (ECG), were found to inhibit HIV-1 integrase effectively as determined by our ELISA method. In our docking study, it is proposed that when the HIV-1 integrase does not combine with virus DNA, the four catechins may bind to Tyr143 and Gln148, thus altering the flexibility of the loop (Gly140-Gly149), which could lead to an inhibition of HIV-1 integrase activity. In addition, after combining HIV-1 integrase with virus DNA, the four catechins may bind between the integrase and virus DNA, consequently, disrupt this interaction. Thus, the four catechins may reduce the activity of HIV-1 integrase by disrupting its interaction with virus DNA. The four catechins have a highly cooperative inhibitory effect (IC50=0.1 µmol/L). Our study suggests that catechins with the galloyl moiety could be a novel and effective class of HIV-1 integrase inhibitors.


Assuntos
Síndrome da Imunodeficiência Adquirida/prevenção & controle , Fármacos Anti-HIV/farmacologia , Catequina/química , Catequina/farmacologia , DNA Viral/metabolismo , Inibidores de Integrase de HIV/química , Inibidores de Integrase de HIV/farmacologia , Integrase de HIV/metabolismo , Síndrome da Imunodeficiência Adquirida/economia , Síndrome da Imunodeficiência Adquirida/enzimologia , Fármacos Anti-HIV/química , Fármacos Anti-HIV/economia , Catequina/análogos & derivados , Catequina/economia , Ensaio de Imunoadsorção Enzimática , HIV-1/genética , Humanos , Pirrolidinonas/química , Pirrolidinonas/farmacologia , Raltegravir Potássico
8.
Biochem Pharmacol ; 42(4): 937-45, 1991 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-1651083

RESUMO

Experiments have been performed to characterize guinea-pig peritoneal eosinophil cyclic nucleotide phosphodiesterase (PDE) activity and establish whether it is involved in regulating superoxide (.O2-) generation. Eosinophils were found to contain a predominantly membrane-bound cAMP PDE(s) (92.5 +/- 2.4% of total activity) which was resistant to solubilization with Triton X-100 (1%). This particulate PDE exhibited complex kinetics (Km = 1.3 and 31.4 microM) and was unaffected by cGMP (IC50 greater than 100 microM) or CaCl2 (2 mM) + calmodulin (10 units/mL). Little cGMP PDE activity was detected in either the soluble or particulate fractions. Inhibitors of the Ro-20-1724-inhibited (Type IV) cAMP PDE, namely Ro-20-1724 (IC50 = 0.92 +/- 0.43 microM), rolipram (IC50 = 0.20 +/- 0.04 microM) and denbufylline (IC50 = 0.20 +/- 0.01 microM), potently inhibited the particulate cAMP PDE, as did the non-selective inhibitors trequinsin (IC50 = 0.11 +/- 0.02 microM) and AH-21-132 (IC50 = 2.57 +/- 0.02 microM). Eosinophil cAMP PDE was resistant to SK&F 94120 (IC50 greater than 1000 microM), the cGMP-inhibited (Type III) cAMP PDE inhibitor, and the cGMP PDE (Type I) inhibitor, zaprinast, was only weakly active (IC50 = 35.33 +/- 10.74 microM). .O2- release from resting cells was potently inhibited by rolipram (IC50 = 0.05 +/- 0.03 microM) and denbufylline (IC50 = 0.06 +/- 0.04 microM) but surprisingly, in view of its potent cAMP PDE inhibitory activity, was only weakly decreased by trequinsin (IC50 = 8.0 +/- 2.7 microM). AH-21-132 (IC50 greater than 10 microM), SK&F 94120 (IC50 greater than 10 microM) and zaprinast (IC50 greater than 10 microM) were without effect. Rolipram and denbufylline alone exerted little effect on cAMP in intact cells but, in the presence of 10 microM isoprenaline, potently increased intracellular accumulation (EC50 = 0.45 +/- 0.16 and 0.28 +/- 0.08 microM, respectively). Trequinsin and AH-21-132 only weakly enhanced isoprenaline-stimulated cAMP accumulation. Although it induced a marked rise in cAMP only in the presence of isoprenaline, rolipram (50 microM) alone was able to increase the activity ratio of cAMP-dependent protein kinase from 0.24 to 0.84. The results suggest that Ro-20-1724-inhibited cAMP PDE plays a role in regulating eosinophil .O2- generation. The poor correlation between the PDE inhibitory actions of certain compounds and their effectiveness in elevating cAMP and inhibiting .O2- suggests the existence of a barrier impeding access to the enzyme.


Assuntos
3',5'-AMP Cíclico Fosfodiesterases/sangue , Eosinófilos/enzimologia , Superóxidos/metabolismo , Animais , Cálcio/metabolismo , Membrana Celular/enzimologia , AMP Cíclico/sangue , Cobaias , Líquido Intracelular/metabolismo , Isoproterenol/farmacologia , Masculino , Inibidores de Fosfodiesterase/farmacologia , Proteínas Quinases/efeitos dos fármacos , Pirrolidinonas/farmacologia , Rolipram
9.
Laryngol Rhinol Otol (Stuttg) ; 67(3): 132-5, 1988 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-3374227

RESUMO

The animal experiment described in this report was conducted to study the effect of piracetam on the blood flow of the inner ear. Blood flow was measured indirectly by means of hydrogen clearance using the polarographic microanalysis technique. A group of twelve crossbred male and female guinea pigs were given 400 mg/kg body weight piracetam (2 ml/kg body weight of commercial solution for injection) by intravenous injection, and hydrogen clearance was measured before and after administering the study drug at the round window in the scala media at the base of the cochlea. Twelve animals in an control group were given an equal volume of physiological saline instead of the study drug. The H2 clearance measurements were taken before and after intravenous injection of saline. The operation and clearance measurements were performed under injection anaesthesia with 2.5 mg. diazepam and 25 mg. pentobarbital sodium, each per kg body weight. The guinea pigs were premedicated with atropine (0.5 mg./kg. body weight i.p.) and, after tracheotomy, were relaxed with pancuronium bromide (1 mg./kg. body weight i.v.) and respirated with a pneumatic respiration pump and the parameters blood pressure, pH and blood gases (pO2, pCO2) were continuously recorded. The results show that intravenous injection of piracetam in the above mentioned dose accelerates hydrogen clearance processes at the base of the cochlea from 8.68 +/- 3.48 to 5.37 +/- 2.05 minutes half-life. This effect is statistically significant (p less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Orelha Interna/irrigação sanguínea , Piracetam/farmacologia , Pirrolidinonas/farmacologia , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Cóclea/efeitos dos fármacos , Feminino , Cobaias , Hidrogênio , Infusões Intravenosas , Masculino , Microcirculação/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos
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